Photographing optical lens assembly, imaging apparatus and electronic device

Abstract

An imaging apparatus includes a photographing optical lens assembly and an image sensor. The photographing optical lens assembly includes a plurality of lens elements. The plurality of lens elements includes, in order from an object side to an image side, a first lens element, a second lens element and a last lens element. Each of the lens elements has an object-side surface facing the object side and an image-side surface facing the image side. At least one of the lens elements is plastic and at least one of the lens elements has at least one inflection point. There is at least one variable axial distance between adjacent lens elements thereof.

What is claimed is: 
     
       1. An imaging apparatus, comprising a photographing optical lens assembly and an image sensor;
 the photographing optical lens assembly comprising a plurality of lens elements which is at least eight and at most ten lens elements, the plurality of lens elements comprising, in order from an object side to an image side, a first lens element, a second lens element and a last lens element; each of the plurality of lens elements having an object-side surface facing the object side and an image-side surface facing the image side, and the image sensor being disposed on the image side of the last lens element; 
 wherein the object-side surface of a seventh lens element is convex in a paraxial region thereof, at least one of the lens elements is plastic, and at least one of the lens elements comprises at least one inflection point; there is at least one variable axial distance between two adjacent lens elements thereof; 
 wherein a minimum among Abbe numbers of the lens elements of the photographing optical lens assembly is Vdmin; the photographing optical lens assembly comprises an object distance between an imaged object and the object-side surface of the first lens element; when the object distance is infinite, an axial distance between the object-side surface of the first lens element and the image sensor is TLinf, a focal length of the photographing optical lens assembly is finf, and an any one of the at least one variable axial distance is ATinf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro, and the axial distance between the object-side surface of the first lens element and the image sensor is TLmacro, an axial distance between the first lens element and the second lens element is smaller than an axial distance between the seventh lens element and an eighth lens element; and the following conditions are satisfied:
   0.60 <TL inf/ f inf<2.50; 
   10.0 <Vd min<28.0; and 
   0.05<|( AT inf− AT macro)/( TL inf− TL macro)|<0.80.
 
 
 
     
     
       2. The imaging apparatus of  claim 1 , wherein the first lens element has positive refractive power, the second lens element has negative refractive power, a maximum among refractive indexes of the lens elements of the photographing optical lens assembly is Nmax, and the following condition is satisfied:
   1.665 <N max<1.780. 
 
     
     
       3. The imaging apparatus of  claim 1 , wherein when the object distance is infinite, the focal length of the photographing optical lens assembly is finf, and an entrance pupil diameter of the photographing optical lens assembly is EPDinf, and the following condition is satisfied:
   1.20 <f inf/ EPD inf<2.0. 
 
     
     
       4. The imaging apparatus of  claim 1 , wherein the minimum among Abbe numbers of the lens elements of the photographing optical lens assembly is Vdmin, and the following condition is satisfied:
   12.0 <Vd min<20.0. 
 
     
     
       5. The imaging apparatus of  claim 1 , wherein a minimum among central thicknesses of the lens elements of the photographing optical lens assembly is CTmin; when the object distance is infinite, the any one of the at least one variable axial distance is ATinf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro, and the following condition is satisfied:
   0.01<|( AT inf− AT macro)|/ CT min<0.50.
 
 
     
     
       6. The imaging apparatus of  claim 1 , wherein when the object distance is infinite, half of a maximum field of view of the photographing optical lens assembly is HFOVinf; when the object distance is 500 mm, half of a maximum field of view of the photographing optical lens assembly is HFOVmacro, and the following conditions are satisfied:
   35.0 degrees<HFOVinf<65.0 degrees; and 
   35.0 degrees<HFOVmacro<65.0 degrees. 
 
     
     
       7. The imaging apparatus of  claim 1 , wherein the photographing optical lens assembly comprises an aperture stop; when the object distance is infinite, an axial distance between the aperture stop and the image sensor is SLinf, the axial distance between the object-side surface of the first lens element and the image sensor is TLinf, and the following condition is satisfied:
   0.70 <SL inf/ TL inf<1.0. 
 
     
     
       8. The imaging apparatus of  claim 1 , wherein a sum of central thicknesses of the lens elements is ΣCT, a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, the axial distance between the object-side surface of the first lens element and the image sensor is TLinf, and the following conditions are satisfied:
   0.48 <ΣCT/TL inf<0.80; and 
   5.20 mm<ImgH<10.0 mm. 
 
     
     
       9. The imaging apparatus of  claim 1 , wherein a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, the axial distance between the object-side surface of the first lens element and the image sensor is TLinf, and the following condition is satisfied:
   1.0 <TL inf/ImgH<1.80. 
 
     
     
       10. The imaging apparatus of  claim 1 , wherein a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, the any one of the at least one variable axial distance is ATinf, an axial distance between the image-side surface of the last lens element and the image sensor is BLinf, the focal length of the photographing optical lens assembly is finf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro, the axial distance between the image-side surface of the last lens element and the image sensor is BLmacro, and the following conditions are satisfied:
   0.07<|( AT inf− AT macro)/( BL inf− BL macro)|<0.90; and
 
   0.72<ImgH/ f inf<1.80. 
 
     
     
       11. The imaging apparatus of  claim 1 , wherein the last lens element has negative refractive power; a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, an axial distance between the image-side surface of the last lens element and the image sensor is BLinf, and the following condition is satisfied:
   3.70<ImgH/ BL inf<10.0. 
 
     
     
       12. The imaging apparatus of  claim 1 , wherein the imaging apparatus comprises a first driving device and a second driving device; the image-side surface of the last lens element is concave in a paraxial region thereof and comprises a convex critical point in an off-axial region thereof. 
     
     
       13. The imaging apparatus of  claim 12 , wherein a central region of an image is corrected when at least one of the plurality of lens elements is moved by the first driving device, and a peripheral region of the image is corrected when at least one of the plurality of lens elements is moved by the second driving device. 
     
     
       14. The imaging apparatus of  claim 12 , wherein at least one of the first driving device and the second driving device comprises shape memory alloys or piezoelectric materials. 
     
     
       15. The imaging apparatus of  claim 12 , wherein when the first driving device is actuated, an axial distance between any two lens elements of the photographing optical lens assembly remains the same; the image sensor comprises at least 50 million pixels. 
     
     
       16. The imaging apparatus of  claim 12 , wherein the at least one variable axial distance changes between the two adjacent lens elements when the second driving device moves one of the two adjacent lens elements; when the object distance is infinite, the any one of the at least one variable axial distance is ATinf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro; and the following condition is satisfied:
   0.07 mm<|( AT inf− AT macro)|*10<1.0 mm.
 
 
     
     
       17. The imaging apparatus of  claim 12 , wherein there is a displacement of the second driving device when the first driving device is actuated. 
     
     
       18. The imaging apparatus of  claim 1 , wherein an Abbe number of a lens element of the photographing optical lens assembly is V, and at least two lens elements in the photographing optical lens assembly satisfy the following condition:
     V< 20.0. 
 
     
     
       19. The imaging apparatus of  claim 1 , wherein there is one variable axial distance in the photographing optical lens assembly. 
     
     
       20. The imaging apparatus of  claim 1 , wherein the variable axial distance is disposed on the image side of the sixth lens element. 
     
     
       21. The imaging apparatus of  claim 1 , wherein an axial distance between two adjacent lens elements which are closest to the image sensor is a maximum among all axial distances between adjacent lens elements of the photographing optical lens assembly. 
     
     
       22. The imaging apparatus of  claim 1 , wherein the imaging apparatus comprises an optical image stabilization device. 
     
     
       23. An electronic device, comprising at least two imaging apparatuses facing a same side, wherein the at least two imaging apparatuses comprise:
 a first imaging apparatus, comprising the imaging apparatus of  claim 1 ; and 
 a second imaging apparatus, comprising an optical lens assembly and an image sensor; 
 wherein a field of view of the first imaging apparatus differs from a field of view of the second imaging apparatus by at least 30 degrees.